src/partition/growfs.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <getopt.h>
   6 #include <linux/magic.h>
   7 #include <sys/ioctl.h>
   8 #include <sys/mount.h>
   9 #include <sys/stat.h>
  10 #include <sys/types.h>
  11 #include <sys/vfs.h>
  12
  13 #include "blockdev-util.h"
  14 #include "crypt-util.h"
  15 #include "device-nodes.h"
  16 #include "dissect-image.h"
  17 #include "escape.h"
  18 #include "fd-util.h"
  19 #include "format-util.h"
  20 #include "log.h"
  21 #include "missing.h"
  22 #include "mount-util.h"
  23 #include "parse-util.h"
  24 #include "path-util.h"
  25 #include "pretty-print.h"
  26 #include "strv.h"
  27
  28 static const char *arg_target = NULL;
  29 static bool arg_dry_run = false;
  30
  31 static int resize_ext4(const char *path, int mountfd, int devfd, uint64_t numblocks, uint64_t blocksize) {
  32         assert((uint64_t) (int) blocksize == blocksize);
  33
  34         if (arg_dry_run)
  35                 return 0;
  36
  37         if (ioctl(mountfd, EXT4_IOC_RESIZE_FS, &numblocks) != 0)
  38                 return log_error_errno(errno, "Failed to resize \"%s\" to %"PRIu64" blocks (ext4): %m",
  39                                        path, numblocks);
  40
  41         return 0;
  42 }
  43
  44 static int resize_btrfs(const char *path, int mountfd, int devfd, uint64_t numblocks, uint64_t blocksize) {
  45         struct btrfs_ioctl_vol_args args = {};
  46         int r;
  47
  48         assert((uint64_t) (int) blocksize == blocksize);
  49
  50         /* https://bugzilla.kernel.org/show_bug.cgi?id=118111 */
  51         if (numblocks * blocksize < 256*1024*1024) {
  52                 log_warning("%s: resizing of btrfs volumes smaller than 256M is not supported", path);
  53                 return -EOPNOTSUPP;
  54         }
  55
  56         r = snprintf(args.name, sizeof(args.name), "%"PRIu64, numblocks * blocksize);
  57         /* The buffer is large enough for any number to fit... */
  58         assert((size_t) r < sizeof(args.name));
  59
  60         if (arg_dry_run)
  61                 return 0;
  62
  63         if (ioctl(mountfd, BTRFS_IOC_RESIZE, &args) != 0)
  64                 return log_error_errno(errno, "Failed to resize \"%s\" to %"PRIu64" blocks (btrfs): %m",
  65                                        path, numblocks);
  66
  67         return 0;
  68 }
  69
  70 #if HAVE_LIBCRYPTSETUP
  71 static int resize_crypt_luks_device(dev_t devno, const char *fstype, dev_t main_devno) {
  72         char devpath[DEV_NUM_PATH_MAX], main_devpath[DEV_NUM_PATH_MAX];
  73         _cleanup_close_ int main_devfd = -1;
  74         _cleanup_(crypt_freep) struct crypt_device *cd = NULL;
  75         uint64_t size;
  76         int r;
  77
  78         xsprintf_dev_num_path(main_devpath, "block", main_devno);
  79         main_devfd = open(main_devpath, O_RDONLY|O_CLOEXEC);
  80         if (main_devfd < 0)
  81                 return log_error_errno(errno, "Failed to open \"%s\": %m", main_devpath);
  82
  83         if (ioctl(main_devfd, BLKGETSIZE64, &size) != 0)
  84                 return log_error_errno(errno, "Failed to query size of \"%s\" (before resize): %m",
  85                                        main_devpath);
  86
  87         log_debug("%s is %"PRIu64" bytes", main_devpath, size);
  88
  89         xsprintf_dev_num_path(devpath, "block", devno);
  90         r = crypt_init(&cd, devpath);
  91         if (r < 0)
  92                 return log_error_errno(r, "crypt_init(\"%s\") failed: %m", devpath);
  93
  94         crypt_set_log_callback(cd, cryptsetup_log_glue, NULL);
  95
  96         r = crypt_load(cd, CRYPT_LUKS, NULL);
  97         if (r < 0)
  98                 return log_debug_errno(r, "Failed to load LUKS metadata for %s: %m", devpath);
  99
 100         if (arg_dry_run)
 101                 return 0;
 102
 103         r = crypt_resize(cd, main_devpath, 0);
 104         if (r < 0)
 105                 return log_error_errno(r, "crypt_resize() of %s failed: %m", devpath);
 106
 107         if (ioctl(main_devfd, BLKGETSIZE64, &size) != 0)
 108                 log_warning_errno(errno, "Failed to query size of \"%s\" (after resize): %m",
 109                                   devpath);
 110         else
 111                 log_debug("%s is now %"PRIu64" bytes", main_devpath, size);
 112
 113         return 1;
 114 }
 115 #endif
 116
 117 static int maybe_resize_slave_device(const char *mountpath, dev_t main_devno) {
 118         dev_t devno;
 119         char devpath[DEV_NUM_PATH_MAX];
 120         _cleanup_free_ char *fstype = NULL;
 121         int r;
 122
 123 #if HAVE_LIBCRYPTSETUP
 124         crypt_set_log_callback(NULL, cryptsetup_log_glue, NULL);
 125         crypt_set_debug_level(1);
 126 #endif
 127
 128         r = get_block_device_harder(mountpath, &devno);
 129         if (r < 0)
 130                 return log_error_errno(r, "Failed to determine underlying block device of \"%s\": %m",
 131                                        mountpath);
 132
 133         log_debug("Underlying device %d:%d, main dev %d:%d, %s",
 134                   major(devno), minor(devno),
 135                   major(main_devno), minor(main_devno),
 136                   devno == main_devno ? "same" : "different");
 137         if (devno == main_devno)
 138                 return 0;
 139
 140         xsprintf_dev_num_path(devpath, "block", devno);
 141         r = probe_filesystem(devpath, &fstype);
 142         if (r == -EUCLEAN)
 143                 return log_warning_errno(r, "Cannot reliably determine probe \"%s\", refusing to proceed.", devpath);
 144         if (r < 0)
 145                 return log_warning_errno(r, "Failed to probe \"%s\": %m", devpath);
 146
 147 #if HAVE_LIBCRYPTSETUP
 148         if (streq_ptr(fstype, "crypto_LUKS"))
 149                 return resize_crypt_luks_device(devno, fstype, main_devno);
 150 #endif
 151
 152         log_debug("Don't know how to resize %s of type %s, ignoring", devpath, strnull(fstype));
 153         return 0;
 154 }
 155
 156 static int help(void) {
 157         _cleanup_free_ char *link = NULL;
 158         int r;
 159
 160         r = terminal_urlify_man("systemd-growfs@.service", "8", &link);
 161         if (r < 0)
 162                 return log_oom();
 163
 164         printf("%s [OPTIONS...] /path/to/mountpoint\n\n"
 165                "Grow filesystem or encrypted payload to device size.\n\n"
 166                "Options:\n"
 167                "  -h --help          Show this help and exit\n"
 168                "     --version       Print version string and exit\n"
 169                "  -n --dry-run       Just print what would be done\n"
 170                "\nSee the %s for details.\n"
 171                , program_invocation_short_name
 172                , link
 173         );
 174
 175         return 0;
 176 }
 177
 178 static int parse_argv(int argc, char *argv[]) {
 179         enum {
 180                 ARG_VERSION = 0x100,
 181         };
 182
 183         int c;
 184
 185         static const struct option options[] = {
 186                 { "help",         no_argument,       NULL, 'h'           },
 187                 { "version" ,     no_argument,       NULL, ARG_VERSION   },
 188                 { "dry-run",      no_argument,       NULL, 'n'           },
 189                 {}
 190         };
 191
 192         assert(argc >= 0);
 193         assert(argv);
 194
 195         while ((c = getopt_long(argc, argv, "hn", options, NULL)) >= 0)
 196                 switch(c) {
 197                 case 'h':
 198                         return help();
 199
 200                 case ARG_VERSION:
 201                         return version();
 202
 203                 case 'n':
 204                         arg_dry_run = true;
 205                         break;
 206
 207                 case '?':
 208                         return -EINVAL;
 209
 210                 default:
 211                         assert_not_reached("Unhandled option");
 212                 }
 213
 214         if (optind + 1 != argc)
 215                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 216                                        "%s excepts exactly one argument (the mount point).",
 217                                        program_invocation_short_name);
 218
 219         arg_target = argv[optind];
 220
 221         return 1;
 222 }
 223
 224 int main(int argc, char *argv[]) {
 225         dev_t devno;
 226         _cleanup_close_ int mountfd = -1, devfd = -1;
 227         int blocksize;
 228         uint64_t size, numblocks;
 229         char devpath[DEV_NUM_PATH_MAX], fb[FORMAT_BYTES_MAX];
 230         struct statfs sfs;
 231         int r;
 232
 233         log_setup_service();
 234
 235         r = parse_argv(argc, argv);
 236         if (r < 0)
 237                 return EXIT_FAILURE;
 238         if (r == 0)
 239                 return EXIT_SUCCESS;
 240
 241         r = path_is_mount_point(arg_target, NULL, 0);
 242         if (r < 0) {
 243                 log_error_errno(r, "Failed to check if \"%s\" is a mount point: %m", arg_target);
 244                 return EXIT_FAILURE;
 245         }
 246         if (r == 0) {
 247                 log_error_errno(r, "\"%s\" is not a mount point: %m", arg_target);
 248                 return EXIT_FAILURE;
 249         }
 250
 251         r = get_block_device(arg_target, &devno);
 252         if (r < 0) {
 253                 log_error_errno(r, "Failed to determine block device of \"%s\": %m", arg_target);
 254                 return EXIT_FAILURE;
 255         }
 256
 257         r = maybe_resize_slave_device(arg_target, devno);
 258         if (r < 0)
 259                 return EXIT_FAILURE;
 260
 261         mountfd = open(arg_target, O_RDONLY|O_CLOEXEC);
 262         if (mountfd < 0) {
 263                 log_error_errno(errno, "Failed to open \"%s\": %m", arg_target);
 264                 return EXIT_FAILURE;
 265         }
 266
 267         xsprintf_dev_num_path(devpath, "block", devno);
 268         devfd = open(devpath, O_RDONLY|O_CLOEXEC);
 269         if (devfd < 0) {
 270                 log_error_errno(errno, "Failed to open \"%s\": %m", devpath);
 271                 return EXIT_FAILURE;
 272         }
 273
 274         if (ioctl(devfd, BLKBSZGET, &blocksize) != 0) {
 275                 log_error_errno(errno, "Failed to query block size of \"%s\": %m", devpath);
 276                 return EXIT_FAILURE;
 277         }
 278
 279         if (ioctl(devfd, BLKGETSIZE64, &size) != 0) {
 280                 log_error_errno(errno, "Failed to query size of \"%s\": %m", devpath);
 281                 return EXIT_FAILURE;
 282         }
 283
 284         if (size % blocksize != 0)
 285                 log_notice("Partition size %"PRIu64" is not a multiple of the blocksize %d,"
 286                            " ignoring %"PRIu64" bytes", size, blocksize, size % blocksize);
 287
 288         numblocks = size / blocksize;
 289
 290         if (fstatfs(mountfd, &sfs) < 0) {
 291                 log_error_errno(errno, "Failed to stat file system \"%s\": %m", arg_target);
 292                 return EXIT_FAILURE;
 293         }
 294
 295         switch(sfs.f_type) {
 296         case EXT4_SUPER_MAGIC:
 297                 r = resize_ext4(arg_target, mountfd, devfd, numblocks, blocksize);
 298                 break;
 299         case BTRFS_SUPER_MAGIC:
 300                 r = resize_btrfs(arg_target, mountfd, devfd, numblocks, blocksize);
 301                 break;
 302         default:
 303                 log_error("Don't know how to resize fs %llx on \"%s\"",
 304                           (long long unsigned) sfs.f_type, arg_target);
 305                 return EXIT_FAILURE;
 306         }
 307
 308         if (r < 0)
 309                 return EXIT_FAILURE;
 310
 311         log_info("Successfully resized \"%s\" to %s bytes (%"PRIu64" blocks of %d bytes).",
 312                  arg_target, format_bytes(fb, sizeof fb, size), numblocks, blocksize);
 313         return EXIT_SUCCESS;
 314 }